Has anyone had this scenario occur, and is there a way to fix it? I have had
this happen in both 2003 and 2007:

I am working on a table, and am frequently copying and pasting rows from one
position to another.

Occasionally, pasting rows causes the table to separate into two tables,
even though the pasted rows are still joined to the row above (no paragraph
break between).  Visually, there ls a dark border where the two tables are
separated.  

A header row set to repeat will not repeat after the point where the “split”
is.

Typically this tends to happen when the table has some rows with merged
columns.

Any ideas?